Gwinnett County, Georgia, A Sunbelt Community: The Invention of a Postwar Suburb

The Sunbelt suburbs postwar rise changed the United States political narrative through coalitions and conclaves. Suburban scholars have traced the movement’s social ramifications through various lenses, including White Flight and Urban Renewal. However, suburbanization through a suburb’s viewpoint has remained unexplored. Gwinnett County, Georgia, is a southern suburb that transformed from a rural environment to a substantial political and economic power. Its trajectory is offset by about twenty years from the familiar pattern of suburbanization. Tracing its history raises several questions about United States suburbanization both in the chronology of postwar urban history and the historic dynamics that shaped it. Gwinnett County developed into a modern suburb about twenty years after World War II, so its social and political motivations followed a very different course to modernization. In spite of its delayed development, it became one of the largest suburbs in the south by the end of the twentieth century

T cell aging: naive but not young

The immune system exhibits profound age-related changes, collectively termed immunosenescence. The most visible of these is the decline in protective immunity, which results from a complex interaction of primary immune defects and compensatory homeostatic mechanisms. The sum of these changes is a dysregulation of many processes that normally ensure optimal immune function. Recent advances suggest that old mice can produce fully functional new T cells, opening both intriguing inquiry avenues and raising critical questions to be pursued

The Vocal Breeding Behaviour of Harbour Seals (Phoca vitulina) in Georgia Strait, Canada: Temporal Patterns and Vocal Repertoire

During the breeding season, male harbour seals (Phoca vitulina) produce underwater calls used in intra-sexual competition and advertisement. One call type, called a roar, has been documented in every population of this species that has been studied. Because calls vary in structure and temporal patterns among populations, it can be inferred that regional vocal dialects may exist, and that the influence of local environmental and biological conditions may affect the timing of calls. Breeding calls have only been studied in relatively few locations worldwide; however, the effect of ambient noise on the underwater vocal behaviour of harbour seals has not been studied. I investigated the temporal patterns, structure and complexity of harbour seal breeding calls at Hornby Island, British Columbia. Underwater recordings were made near the south end of Hornby Island in the summer breeding season of 2014 using a single omnidirectional hydrophone while concurrent visual observations were conducted at a nearby site on shore. I investigated the relationships between roars per hour, tide level, ambient noise and time of day. Logistic regression showed that roars were over eight times more likely to be heard during night-time hours than during the day. When roars were heard, roar number was most influenced by time of day and the progression of the breeding season, with more roars heard later into the breeding season. Roar density was inversely related with ambient noise; however, ambient noise and time of day were highly auto-correlated, and therefore the effects of these two variables could not be assessed independently. Whereas harbour seal call timing in other areas has been attributed to tidally-driven haul-out patterns, the tide level at Hornby Island did not statistically correlate with roar density. I hypothesize that ambient noise may be a cause of the strong diel pattern of call density at Hornby Island, and suggest further study to determine the mechanistic link between ambient noise cycles and calling behaviour. Four breeding call types were identified, one of which was the ‘roar’ call described in every population that has been studied. The structure of the roars at Hornby Island was comparable to those of other populations, but displayed wide variation in several parameters. Each of the three non-roar call types were distinguished from roars qualitatively by aural-visual classification, and quantitatively by trained linear discriminants analysis (LDA). Agreement between these two classification systems was 88%, suggesting that the four call types were distinct. The three non-roar call types contained five call subtypes which were also identified through aural-visual and LDA classification. Agreement was slightly lower at 74%, but more variable, suggesting that some call subtypes were more distinct than others. One non-roar call type, the sweep, was distinct from any call previously described for harbour seals worldwide. I suggest that more than one of these call types are used by each individual, supporting the results of a previous study in California which identified several call types produced by harbour seals. If this is the case, then the vocal breeding repertoire of harbour seals at Hornby Island is more complex than that of most previously studied populations. Further study of this population with the ability to localize calls and identify individuals is required to support or refute the hypothesis that individual harbour seals at Hornby Island produce several call types

FABRIC: A National-Scale Programmable Experimental Network Infrastructure

FABRIC is a unique national research infrastructure to enable cutting-edge and exploratory research at-scale in networking, cybersecurity, distributed computing and storage systems, machine learning, and science applications. It is an everywhere-programmable nationwide instrument comprised of novel extensible network elements equipped with large amounts of compute and storage, interconnected by high speed, dedicated optical links. It will connect a number of specialized testbeds for cloud research (NSF Cloud testbeds CloudLab and Chameleon), for research beyond 5G technologies (Platforms for Advanced Wireless Research or PAWR), as well as production high-performance computing facilities and science instruments to create a rich fabric for a wide variety of experimental activities

Diversity of weed flora in wheat depending on crop rotation and fertilisation

The paper analyses weed flora in wheat depending on crop rotation and fertilisation in a twenty-year period. In both studied periods (1990 and 2010) the total of 49 weed species were determined on different variants of crop rotation, while 20 weed species were found in both studies. In the first research period, in 1990, there were 16 differential species, which were not found in 2010, while in the second research, after 20 years,. there were 13 new weed species, which had not been previously determined. In the second research period, the floristic diversity was significantly reduced, and in certain variants of Crop rotation (three-year rotation, unfertilised three-year rotation and twelve-year rotation) the number of species was reduced two times. In both studied periods, the dominant species were weed-ruderal plants, with the significant share of segetal plants, while the most common life forms were therophytes from the T-4 group. Apart from the positive effects of crop rotation and fertilisation on reducing weediness, the paper also focuses on the presence of species important for biodiversity conservation, such as Fumaria officinalis L. from the category of endangered species, as well as seven other species from the category of vulnerable species - Centaurea cyanus L., Consolida regalis S.F.Gray, Papaver rhoeas L., Viola arvensis Mum, Lathyrus tuberosus L., Ranunculus arvensis L. and Lamium amplexicaule L., which are most likely to survive among crops

Functional and Homeostatic impact of Age-Related Changes in Lymph node Stroma

Adults over 65 years of age are more vulnerable to infectious disease and show poor responses to vaccination relative to those under 50. A complex set of age-related changes in the immune system is believed to be largely responsible for these defects. These changes, collectively termed immune senescence, encompass alterations in both the innate and adaptive immune systems, in the microenvironments where immune cells develop or reside, and in soluble factors that guide immune homeostasis and function. While age-related changes in primary lymphoid organs (bone marrow, and, in particular, the thymus, which involutes in the first third of life) have been long appreciated, changes affecting aging secondary lymphoid organs, and, in particular, aging lymph nodes (LNs) have been less well characterized. Over the last 20 years, LN stromal cells have emerged as key players in maintaining LN morphology and immune homeostasis, as well as in coordinating immune responses to pathogens. Here, we review recent progress in understanding the contributions of LN stromal cells to immune senescence. We discuss approaches to understand the mechanisms behind the decline in LN stromal cells and conclude by considering potential strategies to rejuvenate aging LN stroma to improve immune homeostasis, immune responses, and vaccine efficacy in the elderly.113Ysciescopu

Rapid In Situ Characterization of Soil Erodibility With a Field Deployable Robot

Predicting the susceptibility of soil to wind erosion is difficult because it is a multivariate function of grain size, soil moisture, compaction, and biological growth. Erosive agents like plowing and grazing also differ in mechanism from entrainment by fluid shear; it is unclear if and how erosion thresholds for each process are related. Here we demonstrate the potential to rapidly assemble empirical maps of erodibility while also examining what controls it, using a novel “plowing” test of surface-soil shear resistance (r) performed by a semi-autonomous robot. Field work at White Sands National Monument, New Mexico, United States, examined gradients in erodibility at two scales: (i) soil moisture changes from dry dune crest to wet interdune (tens of meters) and (ii) downwind-increasing dune stabilization associated with growth of plants and salt and biological crusts (kilometers). We found that soil moisture changes of a few percent corresponded to a doubling of r, a result confirmed by laboratory experiments, and that soil crusts conferred stability that was comparable to moisture effects. We then compared different mechanisms of mechanical perturbation in a controlled laboratory setting. A new “kick-out” test determines peak shear resistance of the surface soil as a proxy for yield strength. Kick-out resistance exhibited a relation with soil moisture that was distinct from the plowing test and that was correlated with the independently measured threshold-fluid stress for wind erosion. Results show that our new method maps soil erodibility in arid environments and provides an understanding of environmental controls on variations in soil erodibility. (For more information: Kod*lab